A production method for a cover attached to an outer ring of a hub unit including procedures as follows. A nut is supported by a first protrusion of a first mold. By a second protrusion of a second mold, a core bar including a cylindrical section to be inserted into the outer ring is supported. A resin material is injected into a cavity formed by the first mold and the second mold to form a cover including a nut and a core bar. The cover is detached from the second mold by moving the first mold in a direction of being separated from the second mold. After this, the cover is detached from the first mold by pushing out the cover in a die matching direction with a pin disposed in the first mold.

A method for making a carbon fiber wheel rim includes: preparing an outer supporting piece; winding a carbon-fiber yarn around the outer supporting piece to form carbon fiber layers and to constitute an engaging seat preform; connecting an inner supporting piece to the engaging seat preform; connecting a reinforcement piece to the inner supporting piece; winding a carbon-fiber yarn around an assembly of the engaging seat preform, the inner supporting piece and the reinforcement piece to form carbon fiber layers; fixing the assembly with the carbon fiber layers to form an outer frame preform; and cutting the outer frame preform and the engaging seat preform to form a trench and removing the outer supporting piece therefrom.

In a disk wheel, a metal insert member is embedded in a resinous bolt-fastening part having a bolt hole. The insert member includes: an opposing surface which is opposed to a resin member of the bolt-fastening part; a bonding area a bonded to the resin member within the opposing surface; and a non-bonding area within the opposing surface. The non-bonding area is not bonded to the resin member, but extends from the bonding area so as to receive a load generated when the resin member deforms. It is thereby possible to provide a technique to effectively suppress the influence of residual stress remained after molding of the resin member of the bolt-fastening part, and to ensure the strength required for the bolt-fastening part.

The present invention is intended to provide a machine component composed of metal and rubber that results in no increase of material costs for an adhesive or increase of manufacturing costs for metal molding, causes no contamination of the metal mold or generates no foreign matter on the metal mold due to adhesion of the adhesive at the time of molding, causes no failure by separation of the adhesive from a fitting portion at the time of fitting the metal component, and is clean and favorable in appearance. A machine component 1 composed of metal and rubber is formed by applying a thermoset resin adhesive A to a surface of a metal component 2 of a predetermined shape, and vulcanizing and adhering a rubber 3 of a predetermined shape to part of the surface of the metal component 2 by metal molding.